Several Head frames have shared holes. I don't understand why they brought back shared holes to tennis racquets.
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Starting back in the '70s, there have been times 'we' would look at each other and exclaim, "There was NOT a stringer in the room when this racket was designed". Many racket designs don't take the actual stringing process into account. IF the companies realize that many stringers are actually the folks SELLING the rackets, they would consider the difficulty of stringing their products. If a racket is a pain to string, the sales person/stringer is less likely to recommend it.

Having said that, in some cases, a single hole that accommodates two strings would (often) be more structurally sound compared to TWO holes in (close) proximity.

Personally, I think Volkl had couple of decades of the best stringing patterns in the industry(notwithstanding the Catapult experiment .